Field of the Invention
The present invention relates to a scintillator crystal and a radiation detector using this scintillator crystal.
Description of the Related Art
X-ray imaging apparatuses for use in the medical field and the like receive an X-ray transmitted through an object by a scintillator, and detect light emitted from this scintillator by a photo detector.
Japanese Patent Application Laid-Open No. 2013-47334 discusses a scintillator crystal having a phase separation structure constituted by a plurality of columnar crystals (cylinder phases) including a perovskite type oxide material containing the Gd element, and a crystal phase (a matrix phase) located around these columnar crystals. Each of the plurality of columnar crystals contains a rare earth element as a light emission center, and emits light by radiation excitation. In the present disclosure, the scintillator crystal having the phase separation structure in this manner may be referred to as a phase separation scintillator crystal.
A refractive index is different for a material forming the cylinder phases as compared to a material forming the matrix phase in this scintillator crystal. Due to this difference, this scintillator crystal is equipped with an optical waveguide function. The scintillator equipped with the optical waveguide function can reduce crosstalk compared to a scintillator unequipped with the optical waveguide function.